A wide variety of conveyor systems have been developed for use in transporting produce during harvest, cleaning, and packaging. Roller conveyors are commonly used in such applications. Roller conveyors may be used, for example, in produce washing tables, which may include a set of rollers having bristles thereon for contacting the fruit, a retaining wall along the lateral sides of the table to prevent the produce from falling off of the washing table, and a roller driving system that engages the rollers to cause them to convey the produce through the system.
Roller conveyors used to convey articles along a given pathway are generally comprised of plurality of spaced, parallel rollers positioned along and transverse to the pathway. A frame having parallel roller support sections typically supports the rollers. Each roller typically has a shaft or axle that is supported at its opposed ends by the frame support sections. A roller body is provided on each shaft to support the article being conveyed (e.g., produce). A typical conveyor frame includes a pair of spaced, parallel side rails each having a vertical wall with an inner face and an outer face. A plurality of openings are typically provided on each side rail to support the roller shafts, with the openings on one side rail mirroring the openings in the other side rail. The side rails may also be configured to further isolate the drive means from the rollers, e.g., with an upper wall extending outwardly from the upper edge of the vertical wall.
In conventional roller conveyor systems, shafts extend out from both ends of each roller. These shafts are typically supported by the openings in the side rails, and the roller shafts extend through openings in the side rails. The shafts on one side of these systems are simply allowed to idly rotate in place in the openings, while the shafts on the other side extend through the side rail openings where they are engaged to a driving motor through a transmission system.
Conventional roller conveyor systems for a produce washing tables and other systems typically utilize a sprocket system, in which each roller is connected to a sprocket through the retaining wall by a mechanical coupling assembly. It is to be appreciated that the openings in the side rails must be present in order to connect the rollers to the driving mechanism through the mechanical coupling assembly. Unfortunately, the gaps between the rollers and the retaining walls and the openings through the side rails allow the passage of water, cleaning solutions, wax, debris, and other materials. These contaminants may pass from the roller bed through the retaining wall and into the drive system, which may clog or damage the system, requiring cleaning and repair. Conversely, foreign materials may pass into the system and onto the rollers from the outside, potentially contaminating the fruit or other product being conveyed thereon.
Importantly, any gaps between the lateral ends of the rollers and the retaining walls of the conveyor, as well as the holes in the side rails, may act as a collection site for debris and bacteria, which can result in contamination of the produce on the washing table. In some systems, rubber seals or bearings may be provided in the shaft support side wall openings to prevent such contamination, but these may only serve to collect and accumulate undesirable contaminants from the conveyed products. Regular cleaning is therefore necessary to maintain a safe food processing environment and minimize the threat of contamination by harmful microbes such as safe and free of any contaminants such as E. coli and Listeria. Proper cleaning may be onerous and costly to the operator in terms of both labor and down time.
In particular, it is often necessary to disassemble these conveyor systems for effective and thorough cleaning. The disassembly process can be time-consuming and tedious because it may be necessary to disassemble the roller bed and the drive mechanism in order to sufficiently access the interior parts of the conveying system for sanitation and maintenance. The rollers may need to be removed from their mountings on the conveyor system in order to access the surfaces of the roller, the retaining wall and the coupling assembly, where debris may accumulate. Conveyor system drive mechanism components must be thoroughly cleaned on a regular basis to both maintain the conveyor system in proper working order and to prevent bacteria, foreign particulates or other contamination from coming in contact with the food products.
The time required to disassemble and clean and/or repair a conveyor system can result in a loss of production time while the conveyor system is inoperable and a corresponding loss of revenues. Additionally, the drive system and other components may be damaged over time by the continuous accumulation of materials from the roller bed. It is therefore desirable to provide a conveyor system that reduces the risk of debris accumulation in the mechanical system and prevents or reduces contamination of the system.
Unfortunately, experience has shown that even regular and thorough cleaning of produce conveyor systems is often not enough to eradicate E. coli and Listeria because these pathogens are capable of surviving in even the smallest and most remote areas. Because of the potential for contamination of produce on the rollers, and because of the potential for transmission of contaminants from the conveyor rollers to the drive mechanism and vice versa, it is desirable to minimize the number of places where such contaminants may be transmitted or accumulate.
It is therefore desirable to provide a novel conveyor system that addresses such issues.